SGX Sensortech has developed a range of electrochemical sensors for detecting carbon monoxide and hydrogen sulphide.

These sensors are replacements for present-day electrochemical sensors and the electrical properties of the SGX Sensortech sensors will be identical for all applications.

This is because of the electrochemistry of the catalysts used and the mechanical design of the sensor.

SGX-4DT - Industrial Dual Toxic Sensor (CO and H2S)

Application : Portable Multi-Gas Safety Instrument

Performance Characteristics

The performance characteristics of the SGX-4DT are:

Range - 0 - 500ppmCO,0-200ppm H2S

Output Signal -80 ± 30 nA / ppm CO

775 ± 275 nA/ ppm H2S

Linearity - Linear

Repeatability - < ± 3% CO equivalent

< ± 2% H2S equivalent

Response time, t90 - <30 s

Maximum Overload - 2000ppm CO

500 ppm H2S

Long-term output drift - <5% per annum

Recommended Load Resistor - 20ohms

Warranty - 2years

Operating Conditions

The operating conditions of the SGX-4DT are:

Temperature range is -30 to +50°C

Operating humidity is 15 – 90% RH (non-condensing)

Pressure range is 800 mbar to 1200 mbar

Recommended storage temperature is 0 °C to 20°C

Storage life is 6 months in original packing (0 to 25°C)

Intrinsic Safety Data

The intrinsic safety data of the SGX-4DT are:

Maximum at 2000ppm - 0.3mA

Maximum o/c Voltage - 1.3V

Maximum s/c Current <1.0A

Product Dimensions

In the Figures 1,2 and 3 the product is shown with dimensions. Please note all dimensions are in mm and all tolerances ±0.15 mm.

Figure 1.

Figure 2.

Figure 3.

Cross-Sensitivity Data

The cross-sensitivity data is shown in Table 1. Kindly note that this is only for reference purposes and calibration must be done with the actual gas at a known concentration. This device is designed to be RoHS compliant.

Table 1. Cross-sensitivity data for the SGX-4DT

GAS

CONC.

CO

H2S

Hydrogen Sulfide

25 ppm

< 5 ppm

25 ppm

Sulfur Dioxide

5 ppm

0 ppm

< 1 ppm

Hydrogen

100 ppm

< 30 ppm

< 0.0 5 ppm

Nitric Oxide

35 ppm

< 0.1 ppm

< 1 ppm

Carbon Monoxide

300 ppm

300 ppm

< 5 ppm

Nitrogen Dioxide

5 ppm

< 0.1 ppm

0 ppm

Chlorine

15 ppm

0 ppm

0 ppm

Important Notes

Using the recommended circuitry from SGX, all performance is based on conditions at 20°C, 50%RH and 1atm

Sensor performance is based on temperature.

The sensor must not be soldered to the connector pins as this may damage the sensor and thereby invalidate the warranty.

Figure 4. Output temperature coefficient data

Poisoning

SGX sensors are developed to function in various harsh environments and conditions. It is however essential that exposure to high concentrations of solvent vapours is prevented at the time of storage, operation and fitting into instruments. While utilizing sensors on PCBs, it is important to use degreasing agents before the sensor is fitted.

Recommended Circuit

It is important that the amplifier is of instrumentation quality

Capable of low noise and capacitive drive

Input Offset < 500µV

Recommended load resistor is 20 ohm

The ideal practice is to use a low gain in this circuit and utilise a PGA in the microcontroller.

Op amp suggestions: TLC2252, TLC2254

Figure 5. Recommended circuit for SGX-4DT

SGX-4CO - Industrial Carbon Monoxide Sensor

Application : Portable Gas Detectors

Performance Characteristics

The performance characteristics of the SGX-4CO are given below:

Range is 0 – 1000ppm

Output Signal is 70 ± 25nA/ppm

Zero Shift (-40°C to +50°C) is<±12 ppm equivalent

Linearity is within ±5%

Response time, t90is less than30s

Maximum Overload is 2000ppm

Long-term output drift <20% per annum

Recommended Load Resistor 10 ohms

Warranty is 2 years

Operating Conditions

The operating conditions of the SGX-4CO are:

Temperature range is -30 to +50°C

Operating humidity is 15 – 90% RH (non-condensing)

Pressure range is atmospheric ±10%

Recommended storage temperature is 0°C to 20°C

Storage life is 6months in original packing (0 – 25 °C)

Intrinsic Safety Data

The intrinsic safety data of the SGX-4CO are:

Maximum at 2000ppm is 0.3mA

Maximum o/c voltage is 1.3V

Maximum s/c current is <1.0 A

Cross-Sensitivity Data

The cross-sensitivity data are provided in Table 2. Kindly note that this table is just for reference. It is important to perform calibration with the actual gas at a known concentration. This device is designed to be RoHS compliant.

Table 2. Cross-sensitivity data for the SGX-4CO

Gas

CONC.

SGX-4 H2S

Carbon Monoxide

100 ppm

<2 ppm

Sulfur Dioxide

20 ppm

0 pp m

Nitrogen Dioxide

5 ppm

<0.5 ppm

Nitric Oxide

50 ppm

<0.5 ppm

Ammonia

50 ppm

0 pp m

Chlorine

15 ppm

0 pp m

Ethylene

100 ppm

0 pp m

Carbon Dioxide

5000 ppm

0 pp m

Product Dimensions

In Figure 6, the SGX-4CO is shown with dimensions. All dimensions are in mm and all tolerances are ±0.15 mm

Important Notes

The connector pins must not be soldered as this may damage the sensor and thereby invalidate the warranty. Figure 7 shows the output temperature coefficient data

Figure 7. Output temperature coefficient data

Poisoning

SGX sensors are developed for functioning in a broad range of harsh conditions and environments. It is important that high concentration of solvent vapours are avoided, both during storage, fitting into instruments and operation. While using sensors on printed circuit boards (PCBs), degreasing agents should be used prior to the sensor being fitted.

SGX-4H2S - Industrial Hydrogen Sulfide Sensor

Application : Portable Gas Detectors

Performance Characteristics

The performance characteristics of the SGX-4H2S are:

Range - 0 – 100 ppm

Output Signal - 700 ± 250nA/ppm

Zero Shift (-40°C to +50°C) - < ±1 ppm equivalent

Linearity - within 5%

Response time, t90 - <30 s

Maximum overload - 500ppm

Long-term output drift - <20% per annum

Recommended Load Resistor - 10ohms

Warranty - 2 years

Operating Conditions

The operating conditions of the SGX-4H2S are:

Temperature range is -20 to +40°C

Operating humidity is 15 – 90% RH (non-condensing)

Pressure range is Atmospheric ±10%

Recommended storage temperature is 0°C to 20°C

Storage life is 6 months in original packing (0 – 25°C)

Intrinsic Safety Data

Intrinsic safety data include the following:

Maximum at 2000 ppm …………….………..….0.6 mA

Maximum o/c Voltage …………………….…...…0.8 V

Maximum s/c Current …………………………... <1.0 A

Cross-Sensitivity Data

Table 3. shows the cross-sensitivity data. This table is for reference only. Calibration should be carried out with the actual gas at a known concentration. This device is designed to be RoHS compliant.

Table 3. Cross-sensitivity data for the SGX-4H2S

Gas

CONC.

SGX-4 H2S

Carbon Monoxide

100 ppm

<2 ppm

Sulfur Dioxide

20 ppm

0 pp m

Nitrogen Dioxide

5 ppm

<0.5 ppm

Nitric Oxide

50 ppm

<0.5 ppm

Ammonia

50 ppm

0 pp m

Chlorine

15 ppm

0 pp m

Ethylene

100 ppm

0 pp m

Carbon Dioxide

5000 ppm

0 pp m

Important Notes

All performance is based on conditions at 20°C, 50% RH and 1 atm, using SGX recommended circuitry. Sensor performance is dependant on temperature.

Do not solder to the connector pins as this may damage the sensor and thereby invalidate the warranty.

Product Dimensions

All dimensions are in mm and all tolerances are ±0.15 mm.

Poisoning

SGX sensors are developed to operate in an extensive range of harsh environments and conditions. It is however important that exposure to high concentrations of solvent vapours is avoided, both during storage, fitting into instruments and operation. While using sensors on printed circuit boards (PCB’s), degreasing agents should be used prior to the sensor being fitted.

By continuing to browse or by clicking "Accept All Cookies," you agree to the storing of first and third-party cookies on your device to enhance site navigation, analyze site usage, and assist in our marketing efforts.
Find out more.